Advice on bath exhaust vent termination.

[An HI]

Originally Posted by wwalmsley

Just an observation but the last few ft. of the pipe should be wrapped with insulation condensation will occur.Warm pipe cold attic air..

If the total length of exhaust pipe is in the cold attic above the insulation, it should be insulated for its length to prevent interior condensation. I have seen a water filled droop in a flexible plastic pipe that blocked all ventilation. There was about 3/4 quart of water.

If the pipe is run in a heated space, then the last 3 feet at the exterior wall should be insulated with an airtight vapour barrier over it to prevent condensation on the exterior of the duct and consequent dripping. Small amounts of cold air bypass the damper into the duct or the air in the duct become cold (not an insulted damper) and condensation on its exteior occurs.

[Charley L. Bottger]

I be darned if I would of went 15 ft to a side wall with a roof within 3 feet $350.00 for a roofer to do what cut a hole in the roof and install a rain cap duh I would have taken the roofer on the roof and pushed him off and screamed $350.00 just as he hit the ground.
Roof vents of some nature are installed on every roof out there what is the big deal about another one. Sometimes you guys advice is off the wall pun intended

[An HI]

Originally Posted by cbottger

I be darned if I would of went 15 ft to a side wall with a roof within 3 feet $350.00 for a roofer to do what cut a hole in the roof and install a rain cap duh I would have taken the roofer on the roof and pushed him off and screamed $350.00 just as he hit the ground.
Roof vents of some nature are installed on every roof out there what is the big deal about another one. Sometimes you guys advice is off the wall pun intended

Well said. On Monday I inspected a house with a decent quality range hood installed. It ends there.

The installer went against the manufacturer's instructions of 6" diameter (28.3 sq in) or 3 1/4 X 10 (32.5 sq in) ducting. He installed 4" diameter (12.6 sq in) spiral wound aluminized ducting, essentially dryer ducting. It was about 20' to a side wall while a roof vent would have about 3-4' of duct.

Spiral wound duct acts like ducting of 1 size smaller, so this 4" duct is performing like 3" (7.1 sq in) straight smooth duct! So this is essentially a working condition that is 75% smaller than recommended.

It was uninsulated through a cold attic on top of the insulation batts.

Like I said, a decent medium quality range hood only. Wonder how well that will work?

[David C. Macy]

Originally Posted by wwalmsley

Just an observation but the last few ft. of the pipe should be wrapped with insulation condensation will occur.Warm pipe cold attic air..

I have the insulation and plan on insulating the last few feet of exposed pipe. I did the other pipe about a week ago.

[David C. Macy]

Originally Posted by mgratton

http://www.nachi.org/bathroom-ventil...ducts-fans.htm

And the best practice is to slant horizontal runs of duct down toward the exterior outlet to drain any condensation outside, just saying!

Yes, I could of done a better job with that, so I guess it is not the best practice.

[David C. Macy]

Originally Posted by cbottger

I be darned if I would of went 15 ft to a side wall with a roof within 3 feet $350.00 for a roofer to do what cut a hole in the roof and install a rain cap duh I would have taken the roofer on the roof and pushed him off and screamed $350.00 just as he hit the ground.
Roof vents of some nature are installed on every roof out there what is the big deal about another one. Sometimes you guys advice is off the wall pun intended

Lets see, I have a 5 year roof that was professionally done and both chimneys leak, the plumbing vent leaks.

I was able to install through the sidewall myself and did not want to extend through the roof.

I thought the advice that was given was excellent and I appreciated the time others took to help me out.

I will need someone next spring to redo the chimneys and plumbing vent flashing's. The chimneys have leaked since day 1 of the roof install as it seams it penetrates between the flashing and bricks and mortar as no one wants to bend the flashing into the mortar joint and then seal.There are also numerous fractures in the brick and mortar. If anybody in the area wants the job I will pay a proper fee.

[Charley L. Bottger]

Originally Posted by dmacy

Lets see, I have a 5 year roof that was professionally done and both chimneys leak, the plumbing vent leaks.

I was able to install through the sidewall myself and did not want to extend through the roof.

I thought the advice that was given was excellent and I appreciated the time others took to help me out.

I will need someone next spring to redo the chimneys and plumbing vent flashing's. The chimneys have leaked since day 1 of the roof install as it seams it penetrates between the flashing and bricks and mortar as no one wants to bend the flashing into the mortar joint and then seal.There are also numerous fractures in the brick and mortar. If anybody in the area wants the job I will pay a proper fee.

David we install vents through brand new roofs that are a week old all the time I don't suppose there is anything special about your roof if your roof is already leaking what's another leak between friends. Just kidding Sounds like ya need to find a different roofing contractor

[James F. McKee]

Originally Posted by cbottger

I be darned if I would of went 15 ft to a side wall with a roof within 3 feet $350.00 for a roofer to do what cut a hole in the roof and install a rain cap duh I would have taken the roofer on the roof and pushed him off and screamed $350.00 just as he hit the ground.
Roof vents of some nature are installed on every roof out there what is the big deal about another one. Sometimes you guys advice is off the wall pun intended

Looks like Charley wore his cranky pants today ...

[Charley L. Bottger]

Originally Posted by jmckee

Looks like Charley wore his cranky pants today ...

Nah just wanted to rip your shorts knew you would be back, Buddy
Have a Merry Xmas Jim

[Marcel R. Cyr]

I put my vent through the roof 4 years ago which is about 3' above the ceiling and never had a problem.
And anyone charging $350 should be thrown off the roof as Charley said. Took me two hours to install the fan and roof vent.


Mine is not insulated and my roof that I installed 16 years ago and flashing does not leak. Seems like roofers in your area are a little steep in price and don't know what they are doing, just call themselves roofers.

[James F. McKee]

Originally Posted by cbottger

Nah just wanted to rip your shorts knew you would be back, Buddy
Have a Merry Xmas Jim

You too Partner ...will be thinking about You guys on Monday...

[An HI]

Originally Posted by mcyr

I put my vent through the roof 4 years ago which is about 3' above the ceiling and never had a problem.
And anyone charging $350 should be thrown off the roof as Charley said. Took me two hours to install the fan and roof vent.


Mine is not insulated and my roof that I installed 16 years ago and flashing does not leak. Seems like roofers in your area are a little steep in price and don't know what they are doing, just call themselves roofers.

I have seen 2 small (1"+) icicles hanging from a interior fan cover a few years ago. It was a new package home from a major modular home company.

The bathroom was on the north corner of the house with the exterior vent outlet facing north. Got a call from the owner ( my life insurance guy) after a very cold February night.